My problem was not related to \language or \mainlanguage. It was the side-effect of a different mistake: \startnotmode that was not closed by a \stopnotmode. ... \startmode[Info] ... % things to do when mode Info is active \stopmode \startnotmode[Info] ... % things to do when mode Info is not active \stopmode % <-- THE BUG: should be \stopnotmode ... \mainlanguage[it] % without the right \stopnotmode this statement works only when mode Info is not active ... I just copied and pasted \startmode[Info] ... \stopmode changing only \startmode into \startnotmode, but not \stopmode into \stopnotmode. context did not complain for that mismatch, but --mode=Info made the \mainlanguage[it] ignored, because \startnotmode[Info] was not closed. Everything else seemed to work just fine, and the missing italian hyphenation looked like a mistery. Before that I used \doifmode{Info}{ ... } and \doifnotmode{Info}{ ... }: they are less readable but more robust, since a missing brace gets detected by context.

I apologize for the noise. \mainlanguage[it] before \starttext solves the problem.

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Hello list, I'm typesetting XHTML italian text with Context (version 4/4/16).

I've put a \language[it] just after \starttext, but I get words with a wrong hyphenation.

As a patch, I just put \language[it] at the beginning of the xmlsetup that processes the <p> tag, and now words are hyphenated right, following the italian rules.

It looks like \language[it] get reset at some point.

Have you an explanation?